﻿ORIGIN 
  OF 
  THE 
  COLEOPTERA. 
  301 
  

  

  Staphylinidce. 
  — 
  Maxilla 
  with 
  a 
  1-joiuted 
  inner 
  lobe 
  (Xantholinns), 
  or 
  

   the 
  mala 
  broad 
  and 
  setose 
  as 
  in 
  the 
  succeeding 
  families 
  (Platystethus 
  

   and 
  especially 
  Bledius)j 
  maxillarj^ 
  palpi 
  3- 
  and 
  4-jointed. 
  

  

  The 
  Staphylinid 
  type 
  of 
  maxilla 
  is 
  simply 
  a 
  modification 
  of 
  the 
  Cara- 
  

   bid, 
  with 
  a 
  tendency 
  to 
  degeneration 
  in 
  the 
  lower 
  genera 
  (Bledius, 
  etc). 
  

   Many 
  larvae 
  in 
  this 
  family 
  are 
  carnivorous. 
  

  

  Elaieridce. 
  — 
  Maxilla 
  with 
  a 
  2-jointed 
  lobe 
  or 
  mala 
  5 
  the 
  maxillary 
  

   palpus 
  4 
  Jointed, 
  Antennae 
  4-jointed, 
  bifurcate 
  as 
  in 
  Oarabid 
  larvae 
  5 
  

   mandibles 
  toothed. 
  The 
  maxillae 
  of 
  Elater 
  and 
  Athous 
  are 
  free. 
  While 
  

   generally 
  supposed 
  to 
  be 
  vegetable- 
  eaters 
  (as 
  Agriotes), 
  those 
  larvae 
  

   which 
  live 
  under 
  the 
  bark 
  of 
  trees 
  in 
  mines 
  made 
  by 
  Longicorn 
  and 
  

   other 
  borers 
  have 
  been 
  shown 
  by 
  Ratzeburg, 
  Dufour 
  and 
  Perris 
  to 
  be 
  in 
  

   part 
  carnivorous, 
  living 
  on 
  Dipterous 
  and 
  Longicorn 
  larvae, 
  as 
  well 
  as 
  on 
  

   the 
  excrementitious 
  vegetable 
  matter 
  filling 
  the 
  burrows. 
  Perris 
  {Insectes 
  

   du 
  Pin 
  maritime, 
  p. 
  190) 
  has 
  pointed 
  out 
  the 
  close 
  resemblance 
  of 
  the 
  

   mouth-parts 
  of 
  this 
  family 
  to 
  those 
  of 
  the 
  larval 
  Carabidae. 
  

  

  In 
  the 
  Scarabaeidae, 
  Buprestidae, 
  and 
  all 
  the 
  lower 
  families 
  of 
  Ooleo- 
  

   ptera, 
  the 
  maxillae 
  are 
  of 
  a 
  rather 
  simpler 
  type 
  than 
  in 
  the 
  foregoing 
  fam- 
  

   ilies; 
  the 
  maxillary 
  lobe, 
  or 
  mala, 
  being 
  simple 
  and 
  more 
  or 
  less 
  fringed 
  

   with 
  stift* 
  hairs. 
  In 
  the 
  Scarabaeidae 
  (Osmoderma), 
  and 
  in 
  Pyrochroa, 
  

   which 
  is 
  carnivorous, 
  the 
  mouth 
  -parts 
  are 
  as 
  comx)licated 
  as 
  in 
  any; 
  

   but 
  in 
  the 
  Buprestidae 
  and 
  Ohrysomelidae 
  they 
  are 
  less 
  developed, 
  

   while 
  they 
  are 
  most 
  rudimentary 
  in 
  form 
  and 
  size 
  in 
  the 
  wood-boring 
  

   weevils 
  and 
  Scolytids 
  ; 
  the 
  antennae 
  and 
  second 
  maxillae 
  and 
  legs 
  also 
  

   share 
  in 
  the 
  degradation 
  of 
  structure 
  consequent 
  on 
  the 
  burrowing 
  lig- 
  

   nivorous 
  habits 
  of 
  the 
  larvae. 
  

  

  But 
  it 
  is 
  in 
  the 
  so-called 
  hypermetamorphosis 
  of 
  the 
  Meloidae, 
  that 
  of 
  

   the 
  blister 
  beetle 
  (Epicauta) 
  as 
  well 
  as 
  Hornia 
  having 
  been 
  fully 
  de- 
  

   scribed 
  and 
  illustrated 
  by 
  Professor 
  Riley 
  in 
  the 
  First 
  Report 
  of 
  the 
  

   United 
  States 
  Entomological 
  Commission 
  (p. 
  297-302, 
  PI. 
  lY), 
  that 
  we 
  

   have 
  a 
  clew 
  to 
  the 
  probable 
  origin 
  of 
  the 
  difierent 
  types 
  of 
  Coleopterous 
  

   larvae. 
  The 
  metamorphosis 
  of 
  the 
  oil 
  beetle 
  (Meloe) 
  originally 
  dis- 
  

   covered 
  by 
  Siebold 
  and 
  Newport 
  and 
  also 
  Fab 
  re, 
  is 
  described 
  in 
  

   different 
  entomological 
  manuals.^*^ 
  In 
  brief, 
  the 
  larvae 
  of 
  Meloe 
  when 
  

   hatched 
  are 
  very 
  minute, 
  active, 
  six-legged, 
  slender-bodied 
  creatures, 
  

   parasitic 
  on 
  wild 
  bees 
  ; 
  as 
  the 
  legs 
  end 
  in 
  three 
  claws 
  the 
  insects 
  in 
  this 
  

   stage 
  are 
  called 
  " 
  triungulins." 
  These 
  larvae 
  attached 
  to 
  the 
  bees 
  are 
  thus 
  

   carried 
  into 
  the 
  nests 
  of 
  the 
  latter, 
  where 
  they 
  feed 
  on 
  the 
  bee 
  -larvae 
  and 
  

   bee-bread. 
  On 
  becoming 
  fully 
  fed, 
  instead 
  of 
  transforming 
  directly 
  into 
  

   the 
  pupa 
  state, 
  they 
  assume 
  a 
  second 
  (coarctate) 
  larval 
  form, 
  entirely 
  

   unlike 
  the 
  first, 
  the 
  body 
  being 
  cylindrical 
  and 
  motionless, 
  with 
  long 
  

   legs; 
  they 
  then 
  attain 
  a 
  third 
  larval 
  stage, 
  the 
  head 
  small 
  and 
  the 
  body 
  

   thick, 
  cylindrical 
  and 
  footless 
  ; 
  after 
  this 
  they 
  assume 
  a 
  true 
  pupa 
  stage, 
  

   and 
  finally 
  become 
  beetles. 
  

  

  Professor 
  Riley 
  has 
  traced 
  the 
  hypermetamorphosis 
  of 
  the 
  blister 
  

  

  "'See 
  the 
  -writer's 
  " 
  Guide 
  to 
  tlie 
  Study 
  of 
  Insects," 
  pp. 
  477-479, 
  figs. 
  447-451. 
  

  

  